Observation of a one-dimensional state on stepped Cu(775)

Abstract

We report on using high-resolution angle-resolved two-photon photoemission to observe a one-dimensional surface state 0.27 eV below the Fermi level on a stepped Cu(111) surface. The state is dispersive along the step direction but localized perpendicular to the step orientation. The origin of the state may be explained by confinement due to the step-edge potential.